Thread milling machine



w. D. ARCHEA THREAD MILLING MACHINE Filed March 8, 1 5

INVENTOR BY ALTE DARCHEA ATTORNEY 7 Sheets-Sheet 1 Aug; 24, 1937. w. D. ARCHEA THREAD MILLING MACHINE 7 Sheets-Sheet 2 INVENTOR WALTER DARCHER ATTORNEY Filed March 8, 1935 IIIIII IIII Ill! 4 Aug. 24, 1937. w. D. ARCHEA THREAD MILLING MACHINE Filed March 8, 1935 7 Sheet-Sheet 5 5 a w 0 M 1 m x w a a w m w x W h R m F 9 a V06 M 4 9 i a e 7 ll 8 8 W s g a 7 M Q U .wwm i m v 5 I .7 w

INVENTOR WALTER 11 ARCHEA ATTORNEY Au 24, 1937. w. D. ARCHE' A THREAD MILLING MACHINE Filed March 8, 1935 7 Sheets-Sheet 4 INVENTOR WALTER 11. ARCHER ATTORNEY Aug. 24, 1937. w. D. ARCHEA 2,090,992

THREAD MILLING MACHINE I 7 Filed March a, 1935 7 Sheet-Sheet 5 I l F 527.12 T 7 9 -ZOZ v INVENTOR WALTER llARCHEA BY ATTORNEY Aug. 24, 1937. w. D. ARCHEA THREAD MILLING MACHINE 7 She ets-Sheet l 6 Filed March 8, 1935 M 2m Own 0mm 8m 03 O O- 46' IN VENTOR. WALTER I). ARCHER ATTORNEY.

Aug. 24, 1937. w. D. ARCHEA THREAD MILLING MACHINE 7 Sheets- Sheet 7 Filed March 8, 1935 INVENTOR. ALT R D. ARCHEA Gib:

ATTORNEY.

FIZy.ZZ

,7 Patented Aug. 24, 1937 v UNITED STATES PATENT OFFICE.

THREAD MILLING MACHINE I Walter D. Archeaj, Cincinnati, Ohio, assignor to The Cincinnati Milling Machine Company, Cincinnati, Ohio, a corporation or Ohio 5 Application March 8, 1935, Serial No. 10,126

16 Claims: (cit 10-454) This invention relates to metal working machines and more particularly to an improved a machine tool for producing various internal configurations in a work piece.

5 One of the chief objects of this invention is to provide an improved precision thread milling machine which canbe efiiciently utilized for producing short threads of accurate predetermined length Such a machine is particularly useful 10 for cutting to exact length the short multiple threads in bottle molds. Another object of this inventionis the provision of a machnev of the character described which may be selectively set up for efliciently ls cutting spiral grooves, such as threads; annular grooves; or a combination of both. p

' A further object of'this invention is to provide an improved multiple thread index angle selector which may be efficiently utilized in threading machines to simplify indexing the work through the correct angle incorrespondence with the 35 made in" the specific structural details thereof] within the scope of the appended claims without departing from' or exceeding the spirit of the invention. j t

Referring to the specification in which like ref- 40 erence numerals indicate likeor similar parts:

Figure 1 is an elevation of a machine tool embodying the principles of this invention.

Figure 2 is a section on the line. 2-2 of Figure 1 showing the tool supporting and driving means.

45 Figure 3 is a detailed section on the line 3--3 of Figure 2.

Figure 4 is a detailed section as viewed on the line 4-4 of Figure 1 of the means for inter-connecting the tool slide for power movement.

50 Figure 5 is a section through the=-headstock 'of the machine taken on the line 5-5 of Figure 1.

Figure 6 is a detailsection on the line B6 of Figure 1. I

55 Figure? is a detail section taken on the line 1-"! of Figure 5 showing the transmission means for rotating the work and reciprocating the tooL Figure 8 is a section on the line 84-8 of Figure 5, showing 'thedetails of the control'clutch operating .mechanism. v c

Figure 9 -is a detail section on the line 9-9 of Figure 8. v

Figure 10 is a detail view as shown on the line 0-10 of Figure '1 showing the dial means for indicating the angular extent of a thread. v 10 Figure 11 is a section on the line ll-li of Figure 7. J

Figure 12, is a section on the line l2 --l2"tr Figure '7 showing the details of the-yieldable "clutch means of the tool head transmission.

Figure 13 is a section on the line 63-43 of Figure 2.

Figure 14 is a detail view of the trip control mechanism showing the parts in starting position.

Figure 14a is an expanded view of the dog carrying drum showing the graduated scale for positioning the control dogs. I

Figure 14b is a detail elevational view show: ing the relative position between the dogs shown in Figure 14w with respect to the trip plungers, the latter-being shown ina position for cutting threads of less than a full revolution.

Figure 15 is a'detail view of the trip mechanism for axially indexing the trip shaft shown in Figure 14b.

Figures 16 and 17 are detail views showing the clutch trip shaft in other positions when cutting threads involving one'revolution or more.

Figures 18, 19, 20 and 21 are views showing the different positions of the multiple thread index angle selector.

.Figure 22 is an expanded view in plan of the index selector ring showing the-clamping means therefor, and the setting graduations. 40

Figure 23 is an expanded view of a groove hav ing spiral and annular portions which may be formed. in one continuous operation in a work piece in this machine.

One exemplaryembodiment of the invention is shown in Figure 1 of the drawings, and although it is obviousthat this machine may be utilized for various purposes without departing from the principles of this invention, it is especially us'e'ful in forming the internal threads in bottle molds. Due-to the wide range in the styles and sizes of bottles having screw caps, the thread in one case may be single as on small bottles; and in other casesespecially in the larger di -ameters-it may be double, triple, or other multiple threads. It is conventional practice in the bottle making art to start each thread of a multiple thread combination in the radial plane where the next previous thread stopped so that the threads do not as a rule over-lap, with the result that the angular extent of each-thread of a multiple thread combination will be equal approximately to 360 degrees divided by the multiple thread index number. It will therefore be seen that the length of the individual threads of a multiple thread combination is of very short angular extent. This machine is designed and adapted to automatically stop the relative feeding movement between tool and work after the Work has revolved through the proper angle in accordance with the type of thread being cut and regardless of the number. of individual threads of a multiple thread combination.

The machine comprises a bed J0 upon which '20 is mounted a headstock or work support II; and a tailstock or tool supportindicated generally by the reference numeral 2. Separate variable speed prime movers I3 and I4 are provided respectively for rotating the workand rotating the tool, and each prime mover has individual rate control boxes 5 and I6 mounted respectively on opposite ends of the bed. Each control box has a rheostat which is controlled, as by handles l1 and I3 respectively. In other words, eachof these handles has a stop positionQandis progressively movable from this position to start the motor and gradually increase the speed-thereof to the desired rate.

The tool spindlet I3 is journaled in a longitudinally movable quill 20, and projects beyond one end of the quill for receiving the driving member 2| which may be in the form of a multiple belt pulley. As shown in Figure 2, the driving member 2l-is connected by a motion trans-- mitting band 22 to a source of power such as the pulley 23 secured. to the armature shaft 24 of the variable speed motor 4. The motor I4 is supported or otherwise secured to a plate 24' which is pivotally supported on the pin 25 mounted in a carrier plate 26. The purpose. of this pivoted plate is to adjust the tension of the power transmitting band 22, and for this purpose an adjustable screw 21 is thread: ed into the lower end of the plate and held in suitable position by a lock nut 28. Since the tension is such as to urge the motor and plate in a counter-clockwise direction as viewedin this figure, it is only. necessary to provide a suitable boss 29 against which the end'of the screw 21 may abut.

The quill 20 is supported in a second carrier plate 30 which is mounted on the opposite side of the upright 3| from the carrier plate 26. This upright has a pair of arcuate guides 32 and 33 f o which are generated-about the center 34. In

the guideway 32 which may be in the form of a rectangular groove as shown 'in Figure 2 for receiving a similarly shaped projection on the side of the carrier plate 33. .A pair of clamping bolts 3] pass through the head 3|, the carrier plate 26 and the carrier plate 30, and the axes of these bolts lie .on the circumferential line 38 which is the center line of the guide 32. The guideway 33 simply comprises apair of 42 which is journaled arcuate slots formed in the sides of the upright 3| through which a pair of clamping bolts 39 pass, these bolts extending through the carrier plate 30 at one end and the carrier plate 26 at the'other end. 5

The two carrier plates are simultaneously adjustable up or down by meansof an elevating J screw 40 which, as shown in-Figure 2, passes through a pivoted block 4| secured to the upper 0f the p ght 3| to'permit lateral move-' 10 ment of the screw during movement of the carrier plates along their arcuate paths, The lower end of the screw passes through anut member at opposite ends in the carrier plates.

, The pairs of clamping bolts 31 and 39 have nuts on one end which are loosened during rotation of the elevating screw by the manually op- 'erable handle'43. The angular position of the head is indicated by the arrow 44 which moves 20 over a scale 45 graduated in degrees attached to the rear of the upright3l. It will thus be seen'that the'cutter spindle may be adjusted a considerable amount above center and a' few degrees below center.. It will also be noted that 25 the prime mover for the cutter spindle is adjusted with it so that the drive pulleys 2-3 and 2| always lie in the'same plane, thereby eliminating complications in the drivebetween prime moverand tool spindle. n p

Since the length of the shank 46 of the cutter or tool may vary depending upon the size of the.

cutter, and therefore project different distances beyond the end of the chuck 41 in which the cutter is secured, means have been provided for 35 adjusting the quill to compensate for this, and as shown in Figure 13, comprises a worm 43'. fixed with. the shaft '43 which is journaled at opposite ends in the carrier plate 30- with'the teeth inter-engaging spiral rack teeth 50 milled 40 in the side of the quill 20. The end of shaft. 43

is hexagon-shaped for receiving a suitable shaped wrench for adjusting the same.

The upright 3| which carries the cutter spindle and the driving means therefor is provided with 4:, suitable guidesurfaces inter-engaging the guide surfaces of the lateral guideway 5| formed on the upper surface of the longitudinally movable slide 52. The slide 3| is moved by a depending nut 53 threaded on a screw 54 fixed against longi- 5n tudinal movement in the boss 55. Theserew 54 is provided wltha hand wheel 56 for efiecting rotation thereof, and also'a dial 5! for indicating the amount of movement imparted to the slide upon rotation of the hand wheel.' In the 5:, operation of the machine the upright 3| is moved laterally to-the left, as viewedin Figure 2, to disengage the cutter from the work; and is moved toward the right to sink the cutter-to the required depth in the work. Since this operam tion is repeated'for each thread, a suitable stop. means has been provided to facilitate this movement, comprising a stop bolt 58 'threadedin the upright 3|, and-a lock nut 53 for securing 'the same in any adjusted position. Upon movement of the upright 3| toward the rlght,-the head of bolt 56 abuts the end of a hardened pin 60 located in the boss 55. When this contact is lnade, the tool has been .sunk to the proper depth in the -WOI"k.' Y

The support 52 for the cross slide is suitably guided upon the bed HI and is utilized for moving the cutter toward and'from the work, the slide being shown in a retracted or loading position in .Figure' 1. Since the starting point of engagement between the tool and work must be 4 exactly determined, an adjustable stop has been provided for advancing and retracting the slide '5I to thereby move the tool 34 to and from v tion ofslide 52. i

52in addition to its other functions.

provided to limit the approach movement of the cutter. This stop means comprises an adjustable screw 6I threaded in a boss 62 projecting from the rear end of member 52 and a lock nut 63 for securing the screw in adjusted position. The end 64 of the screw abuts the end of a rack bar 65 which extends from the fixed headstock II through the slide 52.

This rack bar is utilized notonly to form part of the stopping means, but also comprises part of the translating means forthe slide 52. 'As

shown in Figure 3, the rack bar 65 has teeth 86 cut in one side thereof which are inter-engaged by a. pinion 61 which is rotatably mounted in anti-friction bearings 68, as more particularly shown in Figure 2. The pinion has inte grally connected therewith a worm wheel 69 which meshes with a worm I8 secured to the end of shaft II, which shaft projects from the side of the slide 52 and is provided with a manually operable hand wheel I2. If the rack bar is fixed, rotation of the hand wheel will cause transla- From the mechanism thus far described it will be seen that manually operable means have been and to this end means have been provided as shown in Figure 4, for locking the slide to the rack bar. This means comprises a reciprocable block I3 having asemi-circularface- I4 for frictionally engaging the side of'the rack bar. This block is connected. to theend of rod 15 and a manually operable handle I6 having a cam face IT is utilized for'exerting pressure on the end of bar 15 and frictionally clamping the slide to the rack bar.

The transmission for effecting; rotation of the work and translation of the tool slide is shown in Figures and 7. The shaft I8, Figure 5, is operatively connected by means of pulley I9, belt 88. and pulley 8I to the armature shaft 82 of the variable speed motor. I3. This shaft has a worm 83 whichin'ter-meshes with a worm wheel 84 secured to the lower end of a vertical shaft 85. A second shaft 88 parallel to the shaft 85 has a-change gear 81 secured to the upper end thereof in mesh with a change gear 88 secured to the upper end of shaft 85' whereby the rate-of operation of the machine may be fur-v ther changed. A removable cover .plate 89 permits access to these gears for reversing them or substituting gears of other ratios for varying the speed of the transmission. Y

The shaft 86 has a second gear 98 secured thereto for rotating the gear 9| and thereby the integrally formed bevcl gear 82. This gevel gear simultaneously rotates a pair of bevel gears 93 and 94 in opposite directions respectively-which "are, mounted for free rotation on the shaft 95.

This shaft has splined thereon ashifter fork 96 whichcarries-clutch teeth on opposite ends there,-

of for inter'eengagement with similarly formed clutch teeth formed on the opposing faces of bevel gears 93 and 94.

This clutch has an intermediate or neutral po- I sition, and power transmitting positions on either sidethereof; and is shifted by a fork 91 which is splined on the shaft 98. A spring pressed detent 99 serves to maintain the shifter fork 91 in any one of its three positions The shaft 95 has a large worm gear I88 keyed thereto for rotating the "worm wheel I8I which,-

as more particularly shown in Figure 7, is secured as by threaded bolts I82 tothe dog carrying v wheel I83. This wheel is keyed at I84 to a sleeve I85 which is journaled in the bearing I86. This. sleeve has keyed thereto a spur gear I81 for driving gear I 88 mounted for free rotation on a shaft I89. -Means have been provided for connecting the gear I88 in different ways to the shaft I89.and for determining rotation of a gear II8.

keyed to the shaft, this gear driving through spur gear II I a rotatable member I I2in which may be secured suitable means for reciprocating the rack bar 65. v

The member I83 is also connected through suit able indexing. means I I3 to the Workdriving spindle II4, this spindle being supported at one end in the bushing II5 carried by the, sleeve I85, and at the other end in the tapered bearing IIB formed in the forward wall of the headstockthus briefly described; it will be seen that the prime mover I3 actuates through achange gear mechanism and a serially arranged reverser two branch transmissions, one of which serves to rotate the work and the other of which serves to.

reciprocate the tool supporting slide, and-since both are actuated from the-same source they may be moved in synchronized relation to one another.

If it is therefore assumed that the member I83 is permanently connected to the work jspindle I I4, the gear I88 permanently connected for rotating gear H8, and the prime mover actuated, that the tool will be moved with respect to the work in such relation that a single internal thread may be formed in the work piece. Having made these assumptions, it is possible to describe-the operation of thej machine for cutting single threads which will now be done. The work is held in an air-operated chuck II! which may be of any suitable commercial form in which the. work is held by a plurality of radially moved jaws II8. These jaws may be connected through suitable mechanism to the draw bar I I8 shown in Figure '7 in such a; manner that movement of the draw bar to the left, for instance, willeflect clamping of the work and may be admitted to opposite ends of the cylinder through pipes I2I and I22 and controlled by the manually operable valve I23 having theopcrating handle I24. A source of fluid pressure may be connected to the supply pipe I25 which terminates in a receiving port in the valve. The leverIM thus constitutes means for controlling the clamping and unclamping of workin the I After the work has been secured in the chuck course depend on .cut, The stop screw H is now adjusted to limit the manual movement of the slide 52 and position the 5 cutter in a proper starting position with respect to the work. The manual movement of the slide 52.is effected by the hand wheel I2 through the mechanism previously described and shown in Figure 3 of the drawings. When the bar 65 abuts the end 64 of the screw 6|, the hand'lever I6 is operated to clamp the slide 52 with the rackbar 65. The relationship of axial movement of the tool per revolution of the chuck or, in other words the number of threads per inch is determined' by interchangeable pairs of threaded members comprising a screw member I26 and nut member'l21'shown more particularly in Figure 7. ,In other words, a screw and nut of the same number of threads per inch as the thread to be cut are selected and detachably secured in the machine. This is accomplished in the following manner: The bar 65 has a reduced rounded portion I28 and at the intersection of this portion with the main portion a pair of flattened. surfaces I29 are formed for interengagement with similar formed surfaces in the end of the-bore of the screw member I26. A nut I30= is threaded on the end of the reduced portion I26 for forcing the screw into engagement with these flattened 30 surfaces to insure that the. screw member will not be rotated by rotation of the nut. The rod 65 is in turn held against rotation by a key roller I30 engaging a spline I3I formed longi-' tudinaily of the bar 65.

w The nut member I2] is mounted in a counterbore I32 formed in the end of member H2 and fixed for rotation therewith as by a key I33 and held in position therewith by the threaded lock-f 'ing member I34. It will now be seen that by removing the locking member I34 and the nut I30 that the screw and nut I26 and I2! may be removed from the machine, and other pairs having different pitch threads substituted therefor.

. It is necessary in the manufacture of bottle molds to start the thread at a predetermined point in the circumference of the mold, such as at the partingfline between the mold sections and if the work is not originally positioned in the chuck to-obtain this relative position, the

work spindle may be manually rotated to this position by means of a hand wheel I35 which is secured to the end of shaft 5 as more particularly shown in Figureii of the d awings. r After the tool has been moved to starting position, and the work properly oriented, the motor I4 is started and the tool sunk to proper depth by rotation of hand wheel 56. The clutch member 06 is then shifted through operation of the hand lever I36 which is secured to the projecting end 00 of shaft I31, as more particularly shown in Figure 8. The inner end of this shaft is supported in a-fixed part "I38 of the casting which is in turn cut away to provide room for the arm I39 which is pinned to the end of shaft I31 for operating the 5 shifter fork 31 through pin I40. Engagement of this clutch on one side causes rotation of the workv and axial movement of the cutter. Trip control means have been provided for stopping the relative movement therebetween, which may varyln 70 increments from a few degrees up to more than two complete revolutions.

After tripping out to stop the advancing movement of the cutter, the reversing clutch is thrown to the opposite side by 'hand to cause return move- 75 ment, and the tripping -mechanism will again the angle of the thread being automatica1ly throw the reversing clutch to neutral position to stop the parts in their original starting position. The slide 52 .may now be retracted by hand to permit re-loading the machine.

A novel trip mechanism has been provided for stoppingrelative advance between the cutter and; work after a predetermined angular movement which is effective for less than a full revolution or greater than one revolution. For purposes of explanation there will be considered first the setup of the mechanism for fractional revolutions of the work head because this is the simplest form. The trip shaft 98 in Figure 8 has a splined projecting end I4I upon which are mounted two trip leversvl42 and I43 which, as shown in Figure 6, are so mounted on the shaft that the arms diverge-from one another.- It will also be noted from Figure 8 that these arms,lie in diiferent planes whereby a trip dog that will operate upon one will not in any way interfere with the other. The trip arm I43 is utilizedfor stopping the return movement and may be designated as the return stop lever and the arm I42 is utilized to stop the cutting or feeding movement and may be designated as the feed stop lever..

Assuming the angle of revolution 'of the work head to be 320 degrees for instance, which it will be noted is less than a complete revolution, the dog wheel I03 is provided with suitable dogs for tripping the respective levers at the com-- pletion of the feeding and return movements.

To this end the dog wheel is provided with a pair of T-slots I44 and I45 formed in its periphery,

and intermediate these T-slots there is provided a series of graduations as more particularly shown in Figures 14b and 14a respectively. The trip dog I46 which actuates the return stop lever I43 is mounted in the T-slot I45 and secured therein by a conventional T-headed bolt I 41 as more particularly shown inFigure 1417. Since the return stop position must be the same as the starting position, and since the starting position must always be the same, the dog wheel I03 may' divergence of the arms I 42 and I43 the dog I46 has a mark or line I48 inscribed thereon which may be utilized for positioning the dog and in this case placed in radial alignment zero graduation. V

The other dog I43 is mounted in the T-slot I44 and is of similar shape to dog I46 with the exception that the actuating portion I49 therewith the of is centrally located with respect to the base of the dog rather than off-set as in dog I46. This relationship is particularly shown in Figures 14a and 14b respectively. This dog also has a locating mark I50 suitably placed thereon'for positioning the same with the aid of the graduations on the dog wheel. The marks I48 and I50 areon adjacent sides ,of'the dogs so that. if bothof these marks were aligned with the zero mark the head would be re ated a complete revolution and stopped. D'ue to the fact, however, that the dog wheel must move through an angle of substantially 8 degrees in order to effect tripping after contacting the trip lever, it is not possible to ch tain a full revoluhon with this simple set-up.

' The dog I49 is alignedwith'the 320 degree graduation as shown in Figure 14a and the dog I46 q aligned with the zerograduation. Attention zo mthe position I42, before it is tripped by the is invitedto the fact that in this. set-up the trip lever I42 is secured to the trip shaft 98 in spaced relation with respect to lever I43, Figure 14b, and in alignment with a mark II appearing near the outer end of the shaft. This will position the arm I42 in the plane of the operating portion of dog I49. 7

When the clutch- 96 is thrown to'ajeedihg p sition, the dog wheel I03 will rotate in the direction of arrow. I52, Figure 14, and will continueto rotate until the trip lever I42 is operated which will thereby rotate shaft 96, and through the splined portion 93 on the shaft will actuate the shifter fork' 91 and move the clutch to a stop position. In other words, the lever I42 will be dog and will be moved to the full line position shown, after tripping by the dog. 1

The return movement is initiated by the operator throwing the lever I36 to continue the movement of the clutchto its opposite position which. will thereby move the trip levers to the dash and dot line position shown in Figure 14. This will move lever I42 completely out of the path of dog I49 and position the. trip arm I43 inethe path of dog" I46 so that upon counter-clockwise rotation of the dog wheel I03 itmay be engaged and the clutch returned to a stop position.

From the foregoing, it will be seen that in.

order to set up the machine for cutting single threads of less than afull revolution, that the operator merely positions the dog I49 to the angular position desired by aid of the graduations on the dog wheel and move the trip lever I42 into alignment with the m'ark I5I. As previously stated, since the stop position is always the same, it is never. necessary to re-adjust the trip lever I43 or the stop dog 6.;

- As an aid to the operator, the 'dog wheel has another series of graduations thereon, as more particularly shown in Figure 1411. which are the same as the previous set of graduations with the exception that the zero mark is at the front of the machine to align with a fixed pointerwhereby the operator may observe during operation of the machinethe amount of angular movement through which the 'head rotates be;

causethe zero mark of the 'flrstset of gradua-.

.tions is really positioned for observation from the back of the machine and therefore of noaid to the operator when he islin the normal machine operating position.

The relative position of the tripping'parts for.

stopping rotation of the work head afterangular movement through ohe'revolution or plus fractions of another is shown in Figure 16.. As previously mentioned, it is necessary first that the dog I49 pass the trip lever I42 without actuating the same duringthe first time around, and toactuate the same the second time around. Additionally, the parts must-be so positioned... that during the return movement the return stop dog will pass triplever I43 the first time and appearing on the shaft 98. The dog I49 is properly positioned at the desiredjangle and the feed rotation started. After the dog I49 passes arm m the first time, the shaft 98' is indexed enemy toward the left to its'dot and dash line position Figure 16, to move the trip levers I42 and I43 to the left. This indexing movement is effected by the following mechanism:

Referring to Figure 8, the shaft 98 has circular rack teeth I54 cut on its periphery for engagement with the gear segment I55. The gear segment is pivotally mounted on a shaft I56 and has'an integral ball-ended lever I5I engaging a slot I58 formed in the periphery of an axially movable sleeve I59. The sleeve is supported by a shaft I60 'and is moved axially relative to the shaft by means of a pin I6I which'is fixed for rotation with the shaft and has a projecting end engaging an internal spiral groove'l62 formed in the sleeve.

The. shaft I60 has a star wheel J63 secured to the projecting end thereof, the fingers H531: and

I63b on the wheel lying in the plane of an oper-f ating dog I64 as more particularly shown in Figure 15. The dog is secured by 'a conventional T-bolt in the T-slot I44, As the dog I64 passes the star wheel, the latter is rotated through an angle of substantially 90 degrees which thereby .25

through the pin I6I and spiral groove' l62 axially -inoves the sleeve- I59 toward the-rights.v sufficient amount to index the shaft-98 and place the trip arm I42 in the plane of its operating dog I49. This not only positibnsthe'parts for tripping the clutch 96 to a stop position to terminate the feed movement, but also moves the lever I43 out of the plane of its operating dog I46 so that when the clutch 96' is engaged for return movement the dog I46 may pass thetri'p.

lever 3' the first time and reversely operate the star wheel the next time. K 3 v. w

Attention is invited to the'faot that the dog F64 actually rotates the star wheel through a greater angle than 90 degrees in order to get past the same, but a spring pressed detent I65, Figure 6,

aids in returning thestar wheel through a small angle after the dog passes. This makes it possible for the star wheel to hem a position to be engaged by the dog I64 on .its return movement.

-The set-up for rotation of the work head through two revolutions or more is shown in Figure 1'7, and the only necessary change is tomove the trip lever I 42 inwardly to a third position in which it abuts the end of lever I43, and then '50 suitably position the dog I49 to the proper angle. In this case, the operation is the same with the except-ion that the dog I64 indexes thestar wheel twice which becomes necessary in order to move the trip lever I42 outwardly into the properplane 5 with its operating dog. This permits the dog I49 to pass the trip lever twice without actuating the same, but will effect actuation thereof the v third time. It also moves the trip .lever I43 a suflicient distance that upon the return movement star wheel must be indexed twice in an opposite direction in order to get the lever I43 back into the plane of its operating dog. I The trip control mechanism just described may beutilized not only for cutting single threads but 5 "also utilized for cutting multiple threads. The

previous description of'machine operation, was

based upon the assumption that the dog wheel I03 was permanently connected to the sleeve I05. and that thegear I00 was permanentlyconnected with the gear I I0-for the purpose of showing how the'mac he may be operated in a simple manner for cutting single threads, When the machine is operated for cutting multiple threads, certain changes in the set-up of the machine have to be -'75 I66 which, asshown in Figure 7,is connected by the key" I61 to the sleeve'I68, thissleeve being keyed to and surrounding the work spindle Ill. The sleeve has a tapered'bore I69 which fits pn the tapered end of the spindle H4 and held in 10 place by the lock nut I10. The sliding clutch I66 is moved back and forth by the manually operable lever I'll which, as shown in Figure 1, is pivotally mounted at I12 ona fixed part of the headstock. A spring actuated plunger I13 serves to 16 normally maintain the clutch in an engaged position.

The dog wheel I03 is provided with a clutch ring I14 fixedly secured to the end of the dog wheel and has clutch teeth of a complementary shape to inter-engage the clutch teeth of member I 66.

ure 1, the workspindle H4 is disconnected from the dog wheel I03 which servesas a driving mem- 'ber therefor, and during this disconnectionthe work fixture I I1 may be rotated by means of the hand wheel 115 secured thereto so as to position v g the work without disturbing the other mechanism.

It will be obvious that the indexing angle will 0 vary in accordance with the number of multiple threads, that is'if a double thread is being cut the work should be indexed 180 degrees, or if a triple thread is being cut the work should be indexed 120 degrees, and so on. Ordinarily, this would require great care on the part of the oper- I threads being cut whereby the indexing becomes a very simple-operation, it merely-requiring the operator to move the lever.I1I to the left as'ufficient amount -to permit independent rotation of 5 the w'ork fixture. then to release. the lever Illand continue the rotary movement by hand wheel I15 until the clutchsnaps into position again. When the clutch snaps into position by the spring pressed plungers I13 this will be the 5 signal that the proper amount of indexing has been effected. The means which simplifies this operation comprisesaguardring I16 which is mounted on and surrounds the clutch ring I18.

This guard ring as shown in Figures 18 to 21' '55inclusive has a plurality of irregular spaced teeth and slots cut therein which are adapted tocooperate with one radially elongated tooth I11of the sliding clutch member I66. In other words,

the guard ring has the tooth'spacings so ar- 0 ranged that as shown in Figure 18- the elongated tooth I11 is prevented from returning to an'en-J gaged position except at two points which are at opposite ends of diameter I11a and therefore 180 degrees apart. 'Thisinsures' that the'operator.

can only index the work by 180 degree increments if theabove' procedure is followed.-

In Figure 19 the guard ring is shown in a circumferentially adjusted position withr'espect'to its supporting clutch member! so as to permit the engagement of tooth I11-in six different circumferential-positions at'the ends of diameters I I11a, H11), and I11c, and thereby permit the cutting of six multiple threads. .InFigure 20 the guard ring is shown in a second adjusted po- 1 sition to permit four indexings per revolution and From this it will be seen that when the r 7 lever I1I is moved to the left as viewed in Figthe cutting of four multiple threads amid Fig.

ure 21 the guard ring is shown in another position to permit the cuttingpf triple threads. The guard ring. is detachably'secured to the clutch ring I14 by a filister-headed screw I18 Figure 22,

and the head of this screw is'inserted in the counter-bore I19 for securing the guard ring in the position shownin Figure 18; in counterbore I for securing the guard ring in a position shown in Figure 19; in counterbore I8I for securing the guard ring in a position shown in Figure 20; and the counterbore I82 for securing the guard ring in the position shown in Figure 21. Suitable markings such as I83 may be made on the guard ring and in suitable position about the j peripheryg thereof, whereby theyare readily observable from the operators position at the front of the machine. I When cutting single threads; the gear. I08 is positively connected to the gear H0 and through the following means. 'The gear H0 is secured as by the key I84 to the shaft I09, and this shaft also has splined thereon the slidable member I85. This member hasan annular groove I86 formed in the periphery thereof in which is fitted a shoe I81 carried at the end of lever I88, Figure 5, the

lever being secured to the shaft I89 which extends through the headstock casing and-provided with a manually operable lever I90. This lever has a knurled hand grip I 9| which is spring mounted in the end thereof to maintain the same in various adjusted positions by engagement with a series of notches 92 formed in the casting, as

more particularly shown in Figure 1. When the.

member I is in the central position shown in Figure 'L'the spring pressed plungrs I93 move radially outward, as shown in ,Figure 12, to" con-' nect the shaft I09 withthe'clutch ring I 94 secured as by bolts I95 to the periphery of the gear I08. It will be noted from Figure 12 that the ends of plungers I93 are tapered on-one side for engaging the tapered side I96 of slots I 91 formed in ring I94. The gear I08 rotates in thedirection of arrow I98 during the feeding movement-and to all intents and purposes this forms a positive driving connection because the spring I99 is sufficiently strong to prevent radially inward move-.

ment of plungers I93 when only imposed with the duty of moving the work support. This constitutes the connection when ordinary spiral threads are being cut. g

' By a simple. adjustment of member I85, the machine may be transformed for cutting closed annular ,grooves,tand'in'this case it is merely necessary to shift the member I85 to the left as viewed in Figure 7. This causes the inner cone surface 200 on theend of member I85 to engage,

the beveled end 20I of plungers I93 and move the same inward to disengage their ends from the 7 slots I 91. without rotating shaft I09.

Itis also possible to cut with'thismachine a groove having a configuration such as that shown in Figure 23 which such as 202, similarlto a has a partly spiral portion, v I spiral thread, and astraight portion or annular portion 203. This irregular shaped groove may be cut in a single continuous operation by this machine and is accomplished by shifting the member I85 to the right as viewed in Figure 7.

In forming this groove the spiral portion is .cut

first and since the plungers I93 can move radially outward, the gear I08 is permitted to drive gear IIO. When the machine is in the starting position a pair'of longitudinallyextending splines or.

This will permit rotation of gear I 08- r grooves 204 formed on the periphery of member I85 are in alignment with a pair of spring pressed plungers 205 more particularly shown in Figure 11, and these plungers have bevel shaped ends 206 which engage the beveled side 201 of the splines 204. The plungers 205lare carried in a circumferentially adjustable member 208 which hasa knurled portion 209 projecting beyond the headstock casting and a plurality of clamping bolts 2I0. 208 is graduated as shown in Figure and a double ended pointer 2I2 is fixed to the end of shaft I 09 which projects through the member 208 When the parts are in a starting position, the

pointer registers with the zero marks. If now, it is desired that the spiral groove shall have a predetermined angular extent 'of any amount'up to 180- degrees, the clampingbolts 2") are loosened and the member 208 rotated until the proper graduation is opposite the'pointer and then the. clamping bolts are re-tightened. The member 208 is rotated in the direction of arrow 2I3, Fig- "ure 11, which thereby causes retraction of the plungers 205 due to their beveled ends which are in such adirection that this retraction can automatically take place. After this adjustment has been made,: the machine. is started and the shaft I09 will rotate in the direction of arrow 2 thereby carrying the sleeve I85 with it, which movement will continue until the splines in the member I85 come opposite-to the plungers 205, at t which time the plungers will snap home into the" grooves and prevent further rotation of member I85-and thereby of shaft I09 which will cause slippage of the clutch ring I94 due to depression of plungers I93, Figure 12, and the inward feed of the cutter spindle will be prevented but the work will continue to rotate and thereby form the straight portion 20 3"of the configuration 40 shown in Figure 23.

Upon reversal of clutch 96 the gear I08 .will be rotated'in a counter-clockwise direction, or in other words opposite to the direction of arrow I98, and since the plungers I93 are at this time depressed and'riding'against the inner bore of clutch r'ing I94 the tool will not be moved until this rotationhas continued a sufiicient amount to permit the plungers I93 to snap radially out ward into the slots I91. When this occurs the shaft I09 will be' positively driven, and this Will cause depression of plungers 205 and thereby rotation of shaft I09 which will then cause return movement of the cutter along a spiral path to its starting position What is claimed is: 1. In an internal milling machine the combination of a work support, a slide movable toward and from the work support, a carrier adjustably mounted in arcuate guideways on the slide, a tool 0 spindle, an adjustable quill for supporting the tool spindle in the carrier, and means, to adjust saidquill in a direction to position the center of the tool coincident with the center of curvature of said arcuate gui ays. r.

5 "'2; In a thread milling machine having a rotatable work support and .a rotatable tool. spindlehaving a cutter mounted on the end thereof; the combination of means for supporting the tool spindle for angular adjustment with respect to 70 the axis of the work support includin'gan upright having arcuate guideways therein, a carrier adjustably mounted in said guideways; a quill supportingthe tool spindle in said carrier for longitudinal adjustment whereby the center 75 of rotation of the cutter may be positioned co- The beveled face 2 of the member '7, incident withthe center of curvature of said guideways, and means for adjusting said carrier including a cooperating screw and nut, one of which is attached tovthefiaarrier, and the other pivotally supported in said upright. 5 3. In a thread milling machine having a ro-V tatable worksupport and a rotatable tool spindle having a cutter mounted on the end ther J of, the combination of means for supportingthe tool spindle for angular adjustment with "re- 10' spect' to the axis ofthe work support including, an upright, having arcuate guideways therein, a carrier adjustably mounted in said guideways, a quill supporting the tool spindle in said carrier for longitudinal adjustment wherebythe center 15 of "rotation of the cutter may'be positioned co incident with the center of curvature of said guideways, means for adjusting said carrier ineluding a-cooperating screw and nut one of which is attached to the carrier, and the other to the upright, manual-means for moving the upright and thereby the spindle to determine the eccentric adjustment of the centerpf rotation ofth tool spindle with respect to the center of the work support, and an adjustabl e stop'for limit- 2 ing said movement.

4. In a thread cutting machine the combination of a headstock, a work supporting spindle journaled in said headstock, a t'ailstock, a tool spindle having a cutter secured to the end thereof journaled in saidtail'stock, means to revolve theaxis of thetool spindle above and below the plane of said work spindle in accordance with the pitch of the thread being cut, means for feeding the tailstock toward and from the head'- stock including a prime mover, motion transmitting means extending, therefrom for rotation of the work spindle, a longitudinally reciprocable'member extending between said stocks, means to connect said member for reciprocation by'said prime'mover, and means to disconnectthe tail.-

stock from said member for manual adjustment .to a work leading position.

5. In a threading machine having awork support and a tool support, and a workspindle and 45 a tool spindle journaled in therespective supports, the-combination of means for efiecting relative movement between saidsuppo'rts to cuta thread in the work including a prime mover carrie'dby one of said supports, branch trans- 50 missions for rotating the work spindle, and for eifecting relative movement between the sup-. ports, a reverser mechanism connecting the; branch transmissions with said prime mover,- and power trip means actuable by one of said branch transmissions fo'rshifting said reverser to a stopposition;

6. Ina threading machine havinga work support and a tool support, and a work spindle and a tool spindle journaled in the'respective sup- '60 i ports, the combination of means for efiecting relative movement between said supports tofcut a thread in the work including ,a prime mover carried by one of said supports, branch transmissions for rotating the work spindle, .and for efiecting relative movement between the supports, a reverser mechanism connecting the branch transmissions with said primemover, power trip nie'ans actuable by one of said. branch transmissions for shifting said reverserto a stop position, and inter-changeable -means in -th'eother branch transmission for varying'the rate of movement of the tool support with respect to a single rotation of the'twork spindle to thereby change the lead of the'screw being cut.

. '7. In a; threading machine having a work support and a tool support, and a work spindle and a tool spindle journaled in the respective supports, the combination of means for effecting relative movement between. said supports to cut .a thread'i'n-the work including a prime mover carried by'one of said supports-branch transmissions for rotating the work spindle and for effecting relative movement'between the sup- 10 ports, a reverser mechanism connecting the branch transmissions with said prime mover, power trip means actuable by one of said branch transmissions for shifting said reverser to a stop position, inter-changeable means in the other branch transmission for varying the rate of movement of the tool support with respect to a single rotation of the work spindle to thereby change the lead of the screw being cut,'one of I said transmissions also having means for index ing the work spindle relative to the powerdriving means whereby multiple threads may be cut in the work.

8. In a threading machine the combination of a work support, a,thread cutting tool, a power driven member operatively? connected for effecting a relative rotation and a relative feeding movement simultaneously between the work support and tool, and means including a multiple threa'd index angle selector between said memher and, the work support, and means to index the work through angles determined by said selector.

9, In a thread cutting machine having a rotatable work support and a thread cutting tool,

, the combination of means'for effecting a relative spiral feeding movement between the support and tool including a power operable member for rotating the work support, a member shiftable between two positions for eifecting connection and 40 disconnection of the power driven member with respect to the work support, means normally maintaining said connection, manually operable means for effecting said disconnection, and additional manually operable means for rotating the work support'during said disconnection to index the work with respect to the driving means for the purpose of cutting multiple threads. 10. In a multiple thread cutting machine having a rotatable work receiving spindle and a threading tool, a. power transmission for-effecting relative movement between the spindle and tool, said transmission including a power rotatable -member, a shiftable member operatively connect-. ed with the work spindle, complementary inter engaging teeth forming a driving connection between saidmembers, manually operable means for retracting said shiftable member, manually operable means for rotating the work when disconnected fromsaid power member, resilient means normally urging said members into mutual engagement, and-means adaptedto bepre-set to prevent said mutualengagement until the work ,has been manually rotated through a predetermined angle dependent upon the number of mul- Y tiple threads to be cut on'the work.

for-indexing said spindle relative to a thread cutting toolwhereby multiple. threads may becut including a first multiple toothed reference member, a second multiple toothed member permanently connected for rotation with the work spindle andslidable'relatlve thereto to effect engagem'ent and dis-engagement of the teeth of said members, and means intervening between 11. In a threading machine havinga rotatable work receiving spindle, the combination of means said members including a tooth and a multiple slotted guard ring. attachedto' the respective members, said multiple slotted ring cooperating with the teeth on one ofsaid members to prevent mutual re-engagementof the teeth until the .work has been rotated through a predetermined angle.

12. In a machine tool having a rotatable work support and a tool support, the combination. of a power operable transmission including a first branch for rotating the work, a second branch,

a shiftabl member having a first position for connecting said second branch to cause a relative spiral feeding movement between the tool and work for thread cutting purposes, and a second position fordisconnecting said second branch whereby the machine is conditioned for cutting annular grooves, means to move said member to a third position, a prepositionable stop for engaging-said member to interrupt said spiral feed movement to limit the length of a spiral'cut, and

ratchet means adapted to yield upon continued rotation of said second branch to eifect continued rotation of the workwithout feeding movement of the. tool whereby an annular groove may be formed in continuity with said spiral groove.

13. In a threading machine having a work support and a tool support, the combination of power operable means for, generating a spiral cutting path between the supports to form a. thread, a clutch in said transmission having'eo motion interrupting' position and power transmitting positions on either side thereof, manually operable means for shifting saidclutch to one of its power transmitting positions, and means for shifting said clutch to a motion interrupting position after a predetermined -relative angular movement between the work support and tool support including a rotatable dog wheel driven by said transmission through said clutch, a trip plunger mounted adjacent the. periphery of said wheel,

motion transmitting means connecting said plunger with the clutch, and graduations on said I dog wheel for prepositioning the trip dog a predetermined angular distance from said trip plunger whereby after rotation of the dog wheel through saidpredeterminedangle the relative spiral movement between the work and tool will be terminated.

14. In a threading machine having relatively,

spiral movement, a trip lever adjustably posi tioned on said trip plunger whereby. it may be" placed in the path of said dog for engagement therewith during the first revolution thereof; or .out of the path of said dog, andmeans subsequently operable after the dog,has passed the trip plunger one. or more times for axiallyindexing said plunger to position the trip lever in the path of said dog whereby said clutchwillnot be shifted until after one or more complete revolutions of the trip-dog.

15. In athreading machine having relatively movable work and tool supports, for generating a spiral-cutting path, the combination with trans-.

movable work and tool supports for generating;

a'spiralcutting path, the combination with transmission means for efiecting saidmovement, of trip operable means for determining the length of said path after one or more revolutions including a trip plunger, a motion interrupting clutch in said transmission operatively connected with said trip plunger, a trip dog movable in accordance with the rotary component of said spiral movement, a trip lever adjustably positioned on said trip plunger whereby it may" be placed in the path of said dog for engagement therewith during the first revolution thereof; or out of the path of said dog, means subsequently operable after the dog has passed the trip plunger one or more timesfor axially indexing said plunger to position the trip lever in the path of said dog whereby said clutch will not be shifted until after one or more complete revolutions of the trip dog, said last named means including a star wheel and a second trip dog movable in unison with the flrstdog, and means operable by the star wheel for indexing said trip shaft.

16. In a threading machine having a work support, the combination of a tool support movable toward and from the work support including a tool spindle, a carrier for supporting the spindle, an upright, means for adjustably mounting the carrier on one side of said upright; a prime mover mounted on said carrier at the opposite side of said upright and with its axis extending in a direction. parallel to the axis of said spindle, a

power transmitting band for transmitting motion to the spindle from said motor, and means to pivotally support said motor on said carrier for adjustment in a direction to vary the tension in said transmitting band.-

WALTER D. ARCHEA.

CERTIFICATE OF CORRECTION.

Patent No. 2,090,992. August 24,1937.

WALTER D. ARCHEA.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 8, first column, line 58, claim 10, after the Word "Work" insert spindle; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 21st day of September, A. D 1957.

Henry Van Arsdale (Seal) Acting Commissioner of Patents 

